Series parallel controller



2 Sheets-Sheet I. E. D. PRIEST. SERIES PARALLEL CONTROLLER.

(No Model.)

No. 533,920. Patented Feb. 12,1895.

WITNE55E5- 09 a J. I

(No Model.) 2 Sheets-Sheet 2.

' E. D. PRIEST.

SERIES PARALLEL CONTROLLER.

No. 533,920. Patented Feb. 12,1895.

FTIE E UNITED STATES PATENT OFFICE.

EDWARD D. PRIEST, OF SCHENECTADY, NEW YORK, ASSIGNOR TO THE THOMSON-HOUSTON ELECTRIC COMPANY, OF BOSTON, MASSACHUSETTS.

SERIES PARALLEL CONTROLLER.

SPECIFICATION forming part of Letters Patent No. 533,920, dated February 12, 1895.

Application filed November 24, 1894- Serial No. 529.813. (No model.)

To aZZ whom it may concern:

Be it known that I, EDWARD D. Parnsr, a. citizen of the United States, residing at Schenectady, in the county of Schenectady and State of New York, have invented certain new and useful Improvements inSeries Parallel Controllers, of which the following is a specification.

My invention relates to controllers for elec- Ic trio motors and especially to those operated by the now well known series-multiple or series-parallel system, in which the motors are first put in series to develop the greatest torque at lowspeed, and afterward are thrown [5 into various combinations of series-multiple and multiple to get higher speeds; and has for its object to provide an apparatus of the kind described which shall operate with ease and efficiency and in which the rotation of the commutating switch shall be continuous in one direction if desired; that is to say, in which from the highest speed to the off position shall be only a single step, thus rendering it unnecessary for theengineer to reverse the action of the controller under ordinary circumstances.

My apparatus is particularly designed for the control of motors in trunk line railway or long distance work,butI do not by this state- 0 ment mean to exclude from its scope ordinary tramway or surface railway work,asit is well adapted to this purpose also.

Briefly stated, my apparatus consists of two cylinders, one of which, the commutating or controlling cylinder for the motors, is adapted to revolve continuously in either direction, while the other, which is used as a switching cylinder for the resistances in ways well understood, does not revolve, but reciprocates 0 about its axis. The two cylinders are geared together, and the relation of the gearing is such that the reciprocating cylinder makes a complete stroke, that is, from one side to the other, or from a position where all of the resistance is in circuit to one in which it is cut out and back again, during a partial revolution of the commutating cylinder; and by a slightly greater movement of the commutating cylinder, the circuit is opened upon the resistance switcliingcylinder, or the resistance cylinder, as it will be hereainfter called.

By this combination of apparatus I get a method of control of electric motors which I believe to be novel, and which consists in the main in the fact thatI am enabled by this arrangement always to open the circuit 'upon the resistance cylinder. I am further enabled to always open the circuit when the resistance is included therein, and lastly, I effect the changes of the motor combinations during the time that the circuitis thus opened, and when the circuit is again closed, the resistance is in and noinjuriousjump orshock to the motorsis experienced. To state the method somewhat more fully,bef0re changing the combination of the motors I introduce into the circuit a resistance (by preference a somewhat high resistance), and then open the circuit. I then make the changes in the motor combinations and with the resistance still in, I close the circuit again, the resistance is cut out, and the motors are operated in their new combination so long as may be desirable. This method is pursued even when the controller is rotated backward.

It may become necessary to stop the train or car before it has attained full headway, and under such circumstances the shortest way may be to turn the controller handle backward; but by the arrangement which I have designed of having the resistance cylinder make a complete reciprocation with every change in running position of the motors, the same result will be attained whether the controlling handle be turned forward or back; thatis to say, the resistance will be in circuit whenever the circuit is being opened and whenever 'the circuit is being closed, being only out of circuit when the controller is in a running position.

I also aim to employ novel methods ofcorn- 9o bining the motors, which will be more fully pointed out in the claims annexed to this specification.

The accompanying drawings show an embodiment of my invention, Figure 1 being a 5 plan partly broken away of my improved controller; Fig. 2, afront elevation partly insection of a portion thereof; Fig. 3, a development of the two cylinders, and Fig. 4 a series of diagrams showing the motor combinations. IOC

In Figs. 1 and 2, Ais the controller or commutating cylinder; B, the resistance cylinder.

C is a bar connecting the handles of the two cylinders. G, H are gears, one of which is mounted at the axis of the crank N of the commutating cylinder and the other upon that cylinder itself. By the proportioning of these two gears the engineer determines what part of the contact shall pass under the brushes during a single revolution of the crank N. F is a similar crank attached to the segment D meshing with a pinion E upon the resistance cylinder 13. I isa handle turning the crank N. An examination of the parts just described will show that with every revolution of the crank N the bar 0 draws the crank F from left to right in Fig. 1, and as the crank N returns to its original position, the bar 0 thrusts the crank F back again; and thus the segment D is reciprocated, rotating the cylinder 13 first in the direction of the arrow, and then back again. Thus for every revolution of the crank N this action is repeated and during each such revolution a determinate part of the contacts upon the cylinder A passes under the brushes.

Referring now to Fig. 3, I show a development of the cylinders, the connections being indicated diagrammatically. The two cylinders are shown with the brushes out of contact. No change in the circuit relations of the motors takes place during the revolution of the commutator cylinder from the time the brushes make contact until it has rotated as far as the dotted line Q, Q; but the contact brushes Z, Z upon the resistance cylinder B progressively touch the short-circuiting plate B (for which may be substituted short-circuiting contacts of any kind, for instance, parallel strips crossconnected, as indicated in Fig. 2). The resistance is gradually reduced by connecting up a greater number of resistances in multiple until, when the brush M touches the plate 13*, it is short-circuited. At all times when there is liability of sparking, as when any of the brushes Z break contact with the short-circuiting plate E the path of the current is around the blow-out magnets B B, indicated in dotted lines, and the only time when they are out of circuit is when both of the brushes L, L, are upon the shortcircuiting plate B Although I have shown series magnets, it is not essential that they should be in the main circuit, but they may be in shunt. These magnets are preferably located within the resistance cylinder, and in order to reduce the resistance and self-induction of the windings, I may arrange them in multiple either by placing the entire coil of each magnet in multiple to its mate, or by having multiple circuits through the coils. Inasmuch as the circuit is never opened upon the commutating cylinder, it is unnecessary to have such magnets for that cylinder.

The paths of the current in the various combinations are as follows: Starting with the trolley K, the current enters by the brush L upon the resistance cylinder, thence to brush Z, through the magnets B thence through the resistances, thence through the magnet 13' to the lead 0 and by this lead to the brush a upon the commutating cylinder, to contact-plate 1, (assuming the brushes to have just made contact,) by cross-connection to contact-piate 6, to the brush d, through the motor No. 1 to the brush d, through the motorNo. l to the brush 1), to the contact-plate 3, by cross-connection to contact-plate 10, to the brush f, through the motor No. 2 to brush h, to contact-plate 14, by cross-connection to contact-plate 8, to brush e, through the motor No.3 to brush 0, to contactplate 5, by cross-connection to contact-plate 12, to brush g, through the motor No. 4 and out at ground. This corresponds to the first or series position shown in Diagram 1, Fig. 4.

When the brushes a, b, &c., reach the dotted line QQ, the resistance cylinder B will have completed the entire reciprocation, and the brushes will be again out of contact after all the resistance has been cut in, thus opening the circuit. \Vhile the circuit is thus broken the brushes momentarily span the gaps between the contact-plates 7 and 8, l3 and 14:, and the combinations areset up as in Diagram 5 of Fig. 4, Diagrams 2, 3 and 4 showing what takes place as the cylinder comes to the position of Diagram 5; that is, the resistance is first cut out leaving the motors all in series as in Diagram 2, and then preparatory to opening the circuit the resistance is again inserted as in Diagram 3, after which the circuit is opened as in Diagram 4. The position shown in Diagram 5 with the brushes bridging the breaks in the contact-plates, throws a shunt around each of the groups of two motors, and thus prevents any destructive spark which would ensue if the contacts were opened upon the commut'ating cylinder. The circuits are as follows, omitting inthis case the resistance cylinder, as its action is identical in all the positions of the commutating switch; The current entering at contact-plate 1, goes by cross-connection to contact-plate 6, to brush (1, through motor No. 1 to brush b, contact-plate 3, by cross-connection to con tact-plate 10, brush f, through motor No. 2 to brush 72, contactplate 14, by cross-connection to contact-plateS, brush c,through motor No. 3,brush 0, contactplate 5, by cross-connection to contact-plate l2, brush g,through motor No.4 to ground ,this being the series circuit, as before traced.

The second circuit starting from contactplate 1, goes to contact-plate 6 by cross-connection, through motorNo. l to contact-plate 3, contact-plate l0, thence through motor No. 2 brush h which at this time is bridging the break between the contact-plates 13 and 14, thence to contact-plate 1 3, by cross-connection to contact-plate 15, brush t'and out at ground, thus forming a shunt circuit around motors Nos. 3 and 4; the shunt circuit around the motors Nos. 1 and 2 being from contact-plate l to contact-plate 6, by cross-connection to contact-plate 7, to brush 6 bridging the break between 7 and 8, and thence, as before, through the motors Nos. 3 and 4 to ground. In this po- ICO sition there is also a path direct from contactplate 1 to ground as follows: from contactplate 1 to contact-plate 6 by cross-connection, by another cross-connection to contact-plate 7, by the brush bridging the break from the contact-plate 7 to contact-plate 8, by crossconnection to contact-plate 1 1, by the brush to contact-plate 13, by cross-connection to contact-plate 15 and out to ground.

The position illustrated in Diagram 6, Fig. 4, occurs when the brushes have passed the breaks between contact-plates 7 and 8, and 13 and 14, and is as follows: The current entering at contact-plate 1, passes by cross-connection to contact-plate 6, through motor No. 1, to contact-plate 3, thence by cross-connection to contact-plate 10, throughmotor No. 2 to contactplate 13, by cross-connection to contact-plate 15, and thence to ground; the path through motors Nos. 3 and 4 is from contact-plate 6 to contact-plate 7 by cross-connection, thence through motor No. 3 to contact-plate 5, by

cross-connection to contact-p1ate 12, through motor N 0. 4E and to ground. In this position the brush L is just about to touch the plate 13 upon the cylinder B and when it does touch, the position is that illustrated in Diagram 7 of Fig. 4; that is, with the resistance in series and the motors in two groups in multiple of two each. The positions illustrated by Diagrams 8, 9 and 10 are the same as to motor combinations and vary only in that while the brushes a, b, &c., are passing from the line Q-Q to the line Q'Q. The resistance cylinder changes first by cutting out the resistance leavingthe motors as in Diagram 8; second, by reinserting the resistance as in Diagram 9, and then breaking the circuit with the resistance all in, as in Diagram 10,, which is the preparatory step to throwing the motors all in multiple. The position illustratedin Diagram 11 is the firststep in this latter process. In Diagram 11, the brushes are upon the line QQ', and bridge over the breaks between the contact-plates 23, 4-5, 9-10 and 11-12. In this position each of the motors has a shunt around it preparatory to throwing it in multiple with the others. The circuit is traced from contact-plate 1- to contact-plate 6, thence through the motor No.1 to contact-plate 3, by the brush b to contact-plate 2, by crossconnection to contact-plate 15 and to ground, starting again from contact'plate 3, by crossconnection to contact-plate 10, then to brush f, through the motor No.2, to brush h, tocontactplate 13, to contact-plate 15 by cross-connec tion and thence to ground. Another circuit leads from contact-plate 1, by cross-connection to contact-plate 6, by another cross connection tocontact-plate 7, to the brush 6, through the motor No. 3, to the brush 0, to contactplates 4 and 5 at the break, thence by crossconnection from contact 4-to contact-plate15, and out at ground; againstarting fromcontact-plate-5, by cross-connection to contactplate 12, thence through motor No. 4 to ground; the other path through the motor No. 4. being from contact-plate 1 to contact-plate 6, by cross-connection to contact-plate 11, and thence through the motor at to ground. In this position, that is, as indicated in Diagram 11 of Fig. at, there are also two paths to ground directly from the contact-plate 1, as follows: by cross-connection to contact-plate 6, by cross-connection to contact-plate 9, by the brushes bridging the break to contact-plate 10, by cross-connection to contact-plate 3, by the brush to contact-plate 2, by cross-connection to contact-plate 15 and out at ground; the second direct path being, by cross-c011- nection to contact-plate 6, by cross-connection to contact-plate 11, by the brush to contact-plate 12, by cross-connection to contactplate 5, by the brush to contact-plate 4, by cross-connection to contact-plate 15, and out at ground. When the brushes have crossed the line Q-Q,, the circuits are all in multiple through the motors and are as follows: from contact-plate l to contact-plate 6, through the motor No. 1, to contact-plate 2, contactplate 15 and out at ground. Starting again from contact-plate 1, the circuit passes to contact-plate 6, thence by cross-connection to contact-plate 9, through motor No. 2, to contact-plate 13, contact-plate 15, and out at ground. The circuit for motor No. 3 is from contact-plate 1 to contact-plate 6, by crossconnection to contact-plate 7, thence through motor No. 3 to contact-plate 4, cross-connection to contact-plate 15 and out at ground; and that for motor No. 4 is from con tact-plate 1 to contact-plate 6, to contact-plate 11, through the motor and out at ground. thus described corresponds to Diagrams 12, 13, 14, 15 and 16, and does not change upon the commutating cylinder after the brushes pass the line QQ', the changes in the relations of the resistance and the motors being effected solely upon the resistance cylinder. The next step after the motors have been thrown in multiple, as in Diagram 12, is to complete the circuit through the resistance, as in Diagram 13, the resistance being then cut out, as in Diagram let, leaving the motors in their last running position. To proceed from this running position to the off position preparatory to throwing the motors in series, the resistance is again inserted, as in Diagram 15, and the circuit is then opened as in Diagram 16. Between Diagrams 16 and 17 the brushes a, b, &'c., are upon the insulated portion R of the cylinder A with the circuit open; and the next step is when these brushes again touch the contact-plates at 1, 3, &c., thus changing the combination of the motors from multiple to series as in Fig. 17, the circuit, however, being still open. By this arrangement I am enabled to pass at once from the final running position at highest speed back to the off position without going through all of the intermediate steps.

The resistances in the various combinations of motors are indicated diagrammatically by triangular figures, the apex of the triangle The position 4, esaeeo pointingin the direction in which the resistance diminishes. For instance, in Diagram 1, the resistance is diminishing preparatory to its being cutout in Diagram 2, while in Diagram 3 the resistance is increasing in amount preparatory to the circuit being opened, as in Diagram 4.

A comparison of the various diagrams in Fig. 4: will illustrate the fact pointed out in the statement of invention,that the resistance increases to a maximum immediately before the circuit is opened, in whichever direction of rotation the controller is being operated; and it also exemplifies a peculiarity of my controller which I believe to be of great value; that is, that there is an off position adjacent to each running positionso that at whatever speed the vehicle on which the motors are is being propelled, the circuit may be broken by a single motion of the operating handle without waiting to run the controller through all of its various speeds, as in some forms of so-called unbroken circuit controllers now in use.

Changes may easily be devised in the arrangements which I have illustrated without departing from the principle of my invention. Other motor combinations, for instance, might be chosen, and the principle might be extended to a greater or less number of motors than the four illustrated; but all such changes I regard as formal and aim to embrace apparatus embodying them in the scope of the claims appended hereto.

With the apparatus described herein I may combine any suitable step-by-step device, such as the star -wheel and friction roller, now often employed; or I may indicate merely by a pointer or index upon a dial the position of the contacts; but all this forms no part of my invention, and is well understood in the art, so that I do not consider it necessary to illustrate or describe such parts of an operative apparatus.

What I claim as new, and desire to secure by Letters Patent of the United States, is-

1. In a series parallel controller for electric motors, a switch for the motors arranged to connect themin various combinations, in series, multiple series or multiple, and a reciprocating resistance switch adapted to out in resistance and open the circuit before each of such changes of combination.

2. In a series parallel controller for electric motors, a switch adapted to connect the motors in various combinations, series, multiple series or multiple, and a reciprocating resistance switch arranged to open the circuit through a resistance before each such change of combination andto close thecircuit through aresistance aftereach combination is effected.

3. In a series parallel controller for electric motors, a switch adapted to connect the motors in various combinations, series, multiple series or multiple, and a reciprocating resistance switch geared to the commutating switch and arranged to open the circuit through a resistance before each changeof combination, and to close the circuit through a resistance after each combination is effected.

4. In a series parallel controller for electric motors, a commutating device or cylinder adapted to couple the motors in series or parallel at will, and a reciprocating resistance cylinder geared to such commutating cylinder and making a complete reciprocation for a definite arc of movement of the commutating cylinder.

5. The method of controlling electric motors herein set out, which consists in closing the circuit through a resistance with the motors in series, then cutting out the resistance leaving the motors in series in a running position, then reinserting the resistance, then opening the circuit, then changing the motors to a multiple series relation by first shunting a part of them and then closing the circuit through a resistance with the motors in multiple series, and then cutting out the resistance.

6. The method of operating electric motors herein set out, which consists in closing the circuit through a resistance with the motors in multiple series, then cutting out the resistance leaving the motors in multiple series as a running position, then reinserting the resistance and breaking the circuit, then changing the motors from series multiple to multiple by first shunting each motor with the circuit still open, then closing the circuit through a resistance, and then cutting out the resistance, leaving the motors all in multiple as their running position.

7. The method of operating electricmotors herein set out, which consists in closing the circuit through a resistance, with the motors all in multiple, then breaking the circuit with the motors still in multiple, then changing the motors to a series position with the circuit still broken, and then closing the circuit through a resistance with the motors in series, and then cutting out the resistance.

'8. The method of operating electric motors herein set out, which consists in closing the circuit through a resistance with the motors in series, then cutting out the resistance leaving the motors in series, then reinserting the resistance, then opening the circuit with the motors still in series, then throwing the motors into multiple series with the circuit still open by shunting some of the motors, then closing the circuit through a resistance with the motors in multiple series, then cutting out the resistance, then reinserting the resistance and opening the circuit, then shunting each of the motors, then throwing them all in multiple, then closing the circuit through a resistance, and finally cutting out the resistance, leaving the motors all in multiple.

9. The method of operating electric motors herein set out, which consists in closing the circuit through a resistance with the motors in series, then cutting out the resistance leaving the motors in series, then reinserting the the motors all in multiple, then reinserting the resistance, then opening the circuit, then changing the motor combination to series, as herein set out.

In Witness whereof I have hereunto set my hand this 23d (lay of November, 189%.

EDlVARD D. PRIEST.

Vitnesses:

B. B. HULL, A. F. MACDONALD. 

